Sunroofs on vehicles, and particularly on automobiles, have proven to be especially popular. Sunroofs offer the benefits of a convertible top, e.g., sunshine and ventilation, while retaining the desirable characteristics of a permanent sedan roof, e.g., structural integrity and durability. However, the use of the sunroof is not without its drawbacks.
When an airstream flowing over the hood of a moving vehicle strikes the abruptly raised surface of the windshield, a low pressure area is formed immediately behind the top of the windshield. An open sunroof often results in an undesirable amount of airflow in the passenger compartment of the vehicle due to the air circulation down through the sunroof caused by this low pressure zone.
In order to lower the level of airflow in the passenger compartment when the sunroof is open, air deflectors are often placed along the front edge of the sunroof opening. These deflectors force the air that is rushing to the low pressure area created by the windshield to move upwardly, so that the airstream is directed beyond the back edge of the sunroof opening. This has the effect of significantly decreasing the level of airflow in the passenger compartment. Additionally, the deflectors act as a rain shield, permitting the sunroof to be partially opened during inclement weather.
Many cars, however, are provided with sunroofs but no air deflectors. Although air deflectors exist which can be secured by means of screws extending through the roof of the car, this installation process is relatively difficult and can result in the formation of rust spots, due to the violation of the integrity of the vehicle's finish. Alternatively, air deflectors are available that can be secured by means of brackets to the track of the sunroof. In addition to the danger that these brackets will be inadvertently detached, or will damage the sunroof track, the brackets interfere with the aesthetic appearance of the car.